Merge tag 'stable/for-linus-3.10-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull Xen bug-fixes from Konrad Rzeszutek Wilk:
- More fixes in the vCPU PVHVM hotplug path.
- Add more documentation.
- Fix various ARM related issues in the Xen generic drivers.
- Updates in the xen-pciback driver per Bjorn's updates.
- Mask the x2APIC feature for PV guests.
* tag 'stable/for-linus-3.10-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/pci: Used cached MSI-X capability offset
xen/pci: Use PCI_MSIX_TABLE_BIR, not PCI_MSIX_FLAGS_BIRMASK
xen: clear IRQ_NOAUTOEN and IRQ_NOREQUEST
xen: mask x2APIC feature in PV
xen: SWIOTLB is only used on x86
xen/spinlock: Fix check from greater than to be also be greater or equal to.
xen/smp/pvhvm: Don't point per_cpu(xen_vpcu, 33 and larger) to shared_info
xen/vcpu: Document the xen_vcpu_info and xen_vcpu
xen/vcpu/pvhvm: Fix vcpu hotplugging hanging.
diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index 4a9be6d..48e8461 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -295,11 +295,10 @@
int pos;
u32 table_offset, bir;
- pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
-
+ pos = dev->msix_cap;
pci_read_config_dword(dev, pos + PCI_MSIX_TABLE,
&table_offset);
- bir = (u8)(table_offset & PCI_MSIX_FLAGS_BIRMASK);
+ bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR);
map_irq.table_base = pci_resource_start(dev, bir);
map_irq.entry_nr = msidesc->msi_attrib.entry_nr;
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 53d4f68..a492be2 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -85,7 +85,29 @@
EXPORT_SYMBOL_GPL(hypercall_page);
+/*
+ * Pointer to the xen_vcpu_info structure or
+ * &HYPERVISOR_shared_info->vcpu_info[cpu]. See xen_hvm_init_shared_info
+ * and xen_vcpu_setup for details. By default it points to share_info->vcpu_info
+ * but if the hypervisor supports VCPUOP_register_vcpu_info then it can point
+ * to xen_vcpu_info. The pointer is used in __xen_evtchn_do_upcall to
+ * acknowledge pending events.
+ * Also more subtly it is used by the patched version of irq enable/disable
+ * e.g. xen_irq_enable_direct and xen_iret in PV mode.
+ *
+ * The desire to be able to do those mask/unmask operations as a single
+ * instruction by using the per-cpu offset held in %gs is the real reason
+ * vcpu info is in a per-cpu pointer and the original reason for this
+ * hypercall.
+ *
+ */
DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
+
+/*
+ * Per CPU pages used if hypervisor supports VCPUOP_register_vcpu_info
+ * hypercall. This can be used both in PV and PVHVM mode. The structure
+ * overrides the default per_cpu(xen_vcpu, cpu) value.
+ */
DEFINE_PER_CPU(struct vcpu_info, xen_vcpu_info);
enum xen_domain_type xen_domain_type = XEN_NATIVE;
@@ -157,6 +179,21 @@
BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info);
+ /*
+ * This path is called twice on PVHVM - first during bootup via
+ * smp_init -> xen_hvm_cpu_notify, and then if the VCPU is being
+ * hotplugged: cpu_up -> xen_hvm_cpu_notify.
+ * As we can only do the VCPUOP_register_vcpu_info once lets
+ * not over-write its result.
+ *
+ * For PV it is called during restore (xen_vcpu_restore) and bootup
+ * (xen_setup_vcpu_info_placement). The hotplug mechanism does not
+ * use this function.
+ */
+ if (xen_hvm_domain()) {
+ if (per_cpu(xen_vcpu, cpu) == &per_cpu(xen_vcpu_info, cpu))
+ return;
+ }
if (cpu < MAX_VIRT_CPUS)
per_cpu(xen_vcpu,cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
@@ -172,7 +209,12 @@
/* Check to see if the hypervisor will put the vcpu_info
structure where we want it, which allows direct access via
- a percpu-variable. */
+ a percpu-variable.
+ N.B. This hypercall can _only_ be called once per CPU. Subsequent
+ calls will error out with -EINVAL. This is due to the fact that
+ hypervisor has no unregister variant and this hypercall does not
+ allow to over-write info.mfn and info.offset.
+ */
err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
if (err) {
@@ -387,6 +429,9 @@
cpuid_leaf1_edx_mask &=
~((1 << X86_FEATURE_APIC) | /* disable local APIC */
(1 << X86_FEATURE_ACPI)); /* disable ACPI */
+
+ cpuid_leaf1_ecx_mask &= ~(1 << (X86_FEATURE_X2APIC % 32));
+
ax = 1;
cx = 0;
xen_cpuid(&ax, &bx, &cx, &dx);
@@ -1603,6 +1648,9 @@
* online but xen_hvm_init_shared_info is run at resume time too and
* in that case multiple vcpus might be online. */
for_each_online_cpu(cpu) {
+ /* Leave it to be NULL. */
+ if (cpu >= MAX_VIRT_CPUS)
+ continue;
per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
}
}
diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c
index 8b54603..3002ec1 100644
--- a/arch/x86/xen/spinlock.c
+++ b/arch/x86/xen/spinlock.c
@@ -364,7 +364,7 @@
int irq;
const char *name;
- WARN(per_cpu(lock_kicker_irq, cpu) > 0, "spinlock on CPU%d exists on IRQ%d!\n",
+ WARN(per_cpu(lock_kicker_irq, cpu) >= 0, "spinlock on CPU%d exists on IRQ%d!\n",
cpu, per_cpu(lock_kicker_irq, cpu));
/*
diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig
index dd4d9cb..f03bf50 100644
--- a/drivers/xen/Kconfig
+++ b/drivers/xen/Kconfig
@@ -141,7 +141,7 @@
config SWIOTLB_XEN
def_bool y
- depends on PCI
+ depends on PCI && X86
select SWIOTLB
config XEN_TMEM
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index d8cc8127..6a6bbe4 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -167,6 +167,8 @@
info->cpu = cpu;
evtchn_to_irq[evtchn] = irq;
+
+ irq_clear_status_flags(irq, IRQ_NOREQUEST|IRQ_NOAUTOEN);
}
static void xen_irq_info_evtchn_init(unsigned irq,
@@ -874,7 +876,6 @@
struct irq_info *info = info_for_irq(irq);
WARN_ON(info == NULL || info->type != IRQT_EVTCHN);
}
- irq_clear_status_flags(irq, IRQ_NOREQUEST|IRQ_NOAUTOEN);
out:
mutex_unlock(&irq_mapping_update_lock);